100 kHz PLEET velocimetry in a Mach-6 Ludwieg tube
Abstract
Picosecond laser electronic-excitation tagging (PLEET) was demonstrated in a Mach-6 Ludwieg tube at a repetition rate of 100 kHz using a 1064 nm, 100 ps burst-mode laser. The system performance of high-speed velocimetry in unseeded air and nitrogen Mach-6 flows at a static pressure in the range of 5–20 torr were evaluated. Based on time-resolved freestream flow measurements and computational fluid dynamics (CFD) calculations, we concluded that the measurement uncertainty of 100 kHz PLEET measurement for Mach 6 freestream flow condition is ∼1%. The measured velocity profiles with a cone-model agreed well with the CFD computations upstream and downstream of the shockwave; downstream of the shockwave the discrepancy between the CFD and experimental measurement could be attributed to a slight nonzero angle of attack (AoA) or flow unsteadiness. Our results show the potential of utilizing 100 kHz PLEET velocimetry for understanding real-time dynamics of turbulent hypersonic flows and provide the capability of collecting sufficient data across fewer tests in large hypersonic ground test facilities.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 10, 2020
- Source ID
- 10.1364/oe.391302
Entities
People
- Josef J. Felver
- Joseph S. Jewell
- Matthew Borg
- Naibo Jiang
- Paul S. Hsu
- Roger Kimmel
- Sukesh Roy
Organizations
- Air Force Research Laboratory